The present invention proceeds from a constructional unit consisting of a hydraulic machine (hydraulic pump or hydraulic motor) having a drive or driven shaft as well as a support by which the hydraulic machine is held, with the interpositioning of material which deadens solid-conducted sound. An electric motor which drives a hydraulic machine which serves as a hydraulic pump can, for instance, also be fastened on the support. By the solid-conducted-sound deadening material, solid-conducted sound from the hydraulic pump and vibrations are to be prevented from being transmitted from the hydraulic pump to the electric motor and possibly an oil reservoir on which there unit consisting of electric motor and hydraulic pump is arranged.
A hydraulic pump the housing of which is held by a support with the interposition of material which deadens solid-conducted sound is known, for example, from the book "Der Hydraulik Trainer", Vol. I., page 296, 1991, published by Mannesmann Rexroth GmbH. In that hydraulic pump, the sound-deadening material is a profiled rubber ring, which is pressed by means of an annular groove which extends around its outer side onto a radially inwardly directed annular projection on the support. Furthermore, it is clamped axially between a clamping ring and a flange which are screwed together. The housing of the pump is attached at its end to the flange. With this type of attachment, the profiled rubber ring must consist of a relatively hard material, as a result of which the transmission of sound waves and vibrations, particularly in the region of low frequencies, is still not avoided to the extent that is frequently asked for today in the discussion concerning the development of noise in hydraulic systems.